(a) Field of the Invention
The present invention relates to a biocompatible pressure sensor, and more particularly, to a biocompatible pressure sensor which can be implanted into a body to wirelessly measure an internal pressure of the body outside the body, and a method of manufacturing the biocompatible pressure sensor.
(b) Description of the Related Art
A biocompatible pressure sensor is implanted into a body and used for measuring an internal pressure of the body. For example, a catheter tip pressure sensor for measuring a pressure of cerebrospinal fluid and a bladder pressure sensor for measuring a pressure of a bladder have been developed, and researches on an ocular pressure sensor for measuring intraocular pressure of a glaucoma patient have also been actively conducted.
A biocompatible pressure sensor may be manufactured by using a process of a micro electro-mechanical system (MEMS). A representative biocompatible pressure sensor includes a piezo-resistive pressure sensor using a piezo-resistive effect and a capacitive pressure sensor for measuring a pressure change based on a change in capacitance.
The piezo-resistive pressure sensor does not require external power, so that the piezo-resistive pressure sensor can be self-powered and has a high frequency response characteristic and excellent linearity. However, the piezo-resistive pressure sensor cannot measure a static pressure, has relatively low sensitivity, and is very sensitive to a temperature change, so a temperature compensation circuit needs to be included.
The capacitive pressure sensor has merits in that a response speed is rapid, the output thereof is less sensitive to change of a pressure and humidity, and both a static pressure and a dynamic pressure can be measured. However, an operation range of the capacitive pressure sensor is a narrow band, a manufacturing process is complex, and influence of a resistance component of a semiconductor and a high frequency parasitic component becomes large when the capacitive pressure sensor is used in a high frequency band, so it is difficult to use the capacitive pressure sensor.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.